Restoring Colorado River Delta Wetlands Yamilett Carrillo-Guerrero University of Arizona, School of Renewable Natural Resources

Colorado River Delta, Mexico California Arizona Sonora Baja California

Ecozones in the Colorado River Delta

The Colorado River Delta, Mexico Critical migratory site and breeding area for sensitive species Recognition: Biosphere Reserve, Ramsar Convention, WHSRN, and NAWCA

The Need for Restoration in the Colorado River Delta * Major causes for wetland loss in the delta: 1. Lack of instream flows 2. Agricultural expansion

The Need for Restoration in the Colorado River Delta * 76 % of delta wetlands were lost in last 100 years. * Invasion of non-native species (Tamarisk spp.)

Protected Species in Mexico and US that occur the Colorado River Delta Yuma Clapper Rail California Black Rail Least Bittern Least Tern Bald Eagle Peregrine Falcon Prairie Falcon Brown Pelican Wood Stork Savannah Sparrow Willow Flycatcher

Natural Restoration of Riparian Areas Water Management Policies and Regulations

Restoring the Colorado River Delta: A Binational Effort Water Management Estimates of 0.5% of annualized mean flow for Riparian Corridor. Three-month spring flow of 3 x 108 m3 every 4 years , and Perennial flow of 4 x 107 m3

Restoring the Colorado River Delta: A Binational Effort Timing and consistency of excess flows. Management Plan for Colorado River delta floodplain

Restoring the Colorado River Delta: A Binational Effort Policies and Regulations Recognition of ecosystem as user entitled to Colorado River water. 2) Environmental quota.

Restoring the Colorado River Delta: A Binational Effort Policies and Regulations Commitment to secure instream flows in the delta. 4) Involvement of local communities in the restoration process.

Restoration Initiatives from Local Communities

Proposals from Delta Communities * Formal commitment of farmers not to take water out of river if an environmental quota was to be established by US and Mexico. * The river and its banks should be declared a protected natural area.

Proposals from Delta Communities * Restore riparian forests along the River. * Conservation easements * Each user should contribute to instream flow needs, proportionally to its use of water.

Pilot Projects of Restoration in the Delta 1. Environmental use of agricultural drainage water 2. Community wetland management and restoration 3. Farmland retirement for wetland restoration

GENERAL PURPOSE To determine if a program to change land uses of farmland could be established in the Colorado River delta, Mexico, with the purpose of restoring wetland areas.

OBJECTIVES a) Assess landowners disposition to change land use from agriculture to wetland restoration projects b) Determine landowners’ disposition to lease their water rights for wetland conservation c) Estimate the costs of a program of retiring the agricultural land.

MEXICO USA Riparian Potential MEXICO Marshland Potential

2. SURVEY * Personal interviews * Duration: 15 min. questionnaire, 1 hour interviews * 32 Farmers contacted in Region 1 (38% area of study) * 16 Farmers contacted in Region 2 (30% area of study)

QUESTIONNAIRE * Pre-tested with farmers outside study area * Topics: a. Farmers’ perception regarding the Colorado River b. Farmland characteristics c. Farmland retirement program d. Rent of water-rights

Region Land (Ha) $ Land ($US/yr) Water $ Water 1- Riparian 229 Land and Water Availability and Costs Region Land (Ha) $ Land ($US/yr) Water $ Water 1- Riparian 229 (566 acres) $298,616 136.5 (1,106 af) $36,991.5 2- Marsh 115 (284 acres) $74,980 77 (624 af) $20,867 Total 344 Ha 850 acres $373,596 213.5 Ha (1,730 af) $57,858.5

International Wildlife Refuge in the Limitrophe Area Proposed by Cocopah Indian Tribal Council Encompass Limitrophe Area-International Boundary (Arizona-Baja California) Purpose: Preserve the Riparian Corridor in the International Boundary US Agencies supporting: USFWS, US Border Patrol US Agencies against: IBWC, BOR? Mexico’s position: Federal Government do not know, Landowner’s in the area want the riparian corridor a protected natural area

Why an International Wildlife Refuge?

CONCLUSIONS Ecosystem restoration is feasible in the Colorado River delta. 2. Restoration process could be embraced and maintained by local communities. 3. Farmers’ participation could yield more hectares restored than land purchases. 4. Rent of Water Rights in Mexico would not be enough to restore the delta.

As functions and values of wetlands in the Colorado River Delta provide benefits that do not consider political boundaries, management and restoration of the delta ecosystem should be worked out as a bi-nationally shared responsibility.

This research was financed with grants from: Sonoran Institute Pronatura Sonora Wallace Foundation Environmental Defense